Edelbrock 750 cfm on a 514 crate engine

[mmichels]

I have a 514 crate motor in my cobra and only use it for street performance. I put a Edelbrock 750 performer and a Edelbrock torker intake on it only to clear the hood. I am having problems getting it leaned out. I put lighter step up springs, and larger metering rods, and smaller jets. Anyone else set these up? What set up works the best??

[blykins]

Is it running too rich or idling too rich? If it's idling too rich, you could change the idle air bleeds. Why'd you pick such a small carb for such a large displacement engine?

[mmichels]

I am a rookie, I thought this carb was plenty big for all around street driving. I know at high RPM's it will probably starve. I can't tell if it is running rich (how do I), but I know it is running rich at idle and I didn't think that there were adjustable air bleeds
I love to try it, can't find them in the manual??

[blykins]

Pull the plugs and see if they're sooty or fouled a little....that would be the easiest way to see what's goin on.

More than likely it doesn't have idle air bleeds....but I was hoping. Usually they're sitting down in the venturis...little screw in brass guys like the jets are.

Some of the more experienced carb guys can tell you what's goin on....if it were mine, I'd swap it out for a good 850/950 Holley or Demon. Something you can tune a little better.

[Back in Black]

My 514 rebuild with Edelbrock Torker 2 intake just dyno-ed at 576 HP and 622 ft-lbs torque, with a Demon 850 carb. The powerband and HP were lowered a bit due to the intake, but VERY good low end/wide band torque was the result.. (a good deal IMO) I had the Demon 850 leaned out as much as possible prior to this, because it seemed to be too much carb. A smaller carb will give you better low end use-ability. The guys at the rebuild shop tuned/cleaned the carb for me for my start-up

I will be going to a 1000 cfm air door and Holley Pro-jection EFI soon, but the computer controls will decide how much air/fuel, so the specific cfm is not necessarily directly related to full useage of same.

[XXQQQME]

From Holley:

(CID) x Max RPM/3456= CFM

Example: 514 x 6000/3456=892.36 CFM

[Nantucket427]

The only way to truely find out what an engine is doing, is with a dyno. The Air/Fuel mixture is almost impossible to set with out running the car on a Dyno.
My car ran awesome before we went to the Dyno. After timing and carb tunning, the car gainned 90 HP at the rear wheels. The best thing is that it is easlier to drive now.

TAKE YOUR CAR TO A CHASSIS DYNO

[Back in Black]

Is whether you need a fuel pressure regulator. I did because the "Holley blue label" pump I have puts out about 14 PSI.. enough for TWO 4 barrels! It was the main cause of my carb woes..(Initial flooding, fuel bowl load-up, etc)

My car should have come with a regulator but did not

[xlr8or]

Idle mixture screws are at the base on the front of the carb but they really only adjust the initial butterfly opening. You'll need to start with jets that are close to correct and go from there. The edelbrock carb uses metering rods with two sizes that sit in the jet to adjust for cruise and WOT. Transition from part to full throttle is controlled by the springs on the metering rods. You can also adjust the accellerator pump if you are stumbling in transition from fuel starvation.
Get it close and then go to the dyno where a/f ratio can be monitored and adjusted as needed. You can buy an adjustment kit with an assortment of jets and metering rods and springs. Take that with you to the dyno. If they are familiar with the Edelbrock or Carter carbs they should be able to dial it in pretty well.